M.×giganteus is a tall, warm-season perennial grass, which has been grown in Europe as a biofuel and bioenergy crop for more than a decade. It is a sterile triploid (3N=57) generated from the hybridization of the diploid M. sinensis (2N=38) with the tetraploid M. sacchariflorus (4N=76) and is characterized as a low input and low maintenance plant with a high yield, little or no susceptibility to pests and diseases, and low moisture and low ash contents at harvest. In comparison with switchgrass, it was reported that M.×giganteus produced 2 times more biomass than switchgrass (Heaton et al., Biomass Bioenergy vol. 27:21-30, 2004). Also, M.×giganteus produces approximately 2.5 times the amount of ethanol than corn does. It has a great leaf area and a long growing season, and can thus gain a great amount of photosynthetic carbon per unit of leaf area (Dohleman and Long, Plant Physiol. vol. 150:2104-2115, 2009). It has been considered as one of the most promising biofuel and bioenergy crops in the US and as an ideal plant for producing fuel ethanol at a lower cost than corn.
M.×giganteus is a sterile hybrid and does not produce viable seeds so it has not been found to be invasive in Europe or the United States. However, plants can only be propagated from rhizomes or through tissue culture-based micropropagation. The cost for producing plants from rhizomes is expensive and low-throughput, yielding low numbers of plants. Hence, more practical and high-throughput protocols are needed to provide the large number of plants for the large-scale plantings required to make this a viable energy crop in the US. In Europe, almost all plants are produced by micropropagation, as plants from rhizome division are too expensive and the propagation rate relatively low (Lewandowski, Micropropagation of Miscanthus×giganteus. In: Biotechnology in Agriculture and Forest, ed. By Bajaj YPS, Springer-Verlag Berlin Heidelberg. Vol. 39: p240-255, 1997).